Four sleeps, two lows, a good dose of rain but no tropical cyclones to go until Christmas
✎ Edit Post
Posted December 21, 2020
Media Release: MetService
MetService is forecasting a cloudy run in to Christmas, with some significant rain and strong winds especially around Christmas Eve. For Christmas Day however a southerly change ushers in clearer skies and cooler temperatures, although areas in the south and east will continue to see showers.
“The main player in our weather is a slab of warm air reaching across New Zealand from the Tasman Sea,” explains MetService meteorologist Tom Adams.
“The remains of ex-tropical cyclone Yasa are still circulating in the Pacific, but the system has been re-classified as an extra-tropical low, is not coming near to New Zealand and will not affect our weather.”
Two low pressure systems form on the southern edge of the warm air in the Tasman Sea however, crossing Aotearoa on Tuesday and on Christmas Eve. The first and smaller of these lows will bring heavy rain to the South Island West Coast, but its effects are muted over the North Island although cloud and the odd shower are still to be expected for most places tomorrow. Cloud and rain stick around on Wednesday, with strengthening northwesterly winds.
The second low will cross on Christmas Eve and has the potential to bring challenging conditions for people travelling between the regions ahead of the holidays. Northerly gales for central New Zealand and heavy rain for the western and upper South Island are all highlighted in the Severe Weather Outlook, and it is likely that Severe Weather Watches and Warnings will be issued closer to the event. Once again though, the upper North Island will see a cloudy and occasionally wet day, but the worst effects will be further south.
The low will have passed by Christmas Day leaving cooler southerly winds behind it. Areas exposed to the southerly such as Dunedin, Christchurch, Wellington and the Kaikoura Coast can expect a few showers, but more western and northern areas like Auckland, Taranaki, Nelson and the Waikato are looking at a drier, sunnier day to start the holidays. The pick of locations that get that combination of warmth and sun for Christmas would be Gisborne, Bay of Plenty of Northland. Another weak front does move up the country on Boxing Day, but overall we see an improving trend through the weekend although unsettled conditions return the following week.